Lisa Gardner’s new book, “Find Her,” explores a high-profile kidnapping and the changing nature of the government’s response to crime. The book will be released Tuesday. That night, Gardner will launch her book tour at Murder By The Book.

Q: You do extensive research for your novels and often select topical issues. How do you choose the topics?
A: The research I did for “Find Her” was something I started with “Catch Me.” It’s related to self-defense, and I think we’re all more conscious about safety and security issues. I attended a writers’ police academy, and we learned self-defense tactics and how to free yourself from handcuffs with a universal handcuff key, which I found online for about $15. Since then, I’ve met law-enforcement and military personnel, and they’re like, “Yeah, we never leave home without those keys.” I think my writing involves facing deep fears. As a mom, child abduction is one of my greatest terrors, and it happens to the main character, Flora, in “Find Her.”

Q: Speaking of Flora, she spends a lot of time locked up in a coffin in your new novel. Did you get into a coffin or some enclosed space to write about that?
A: I’m claustrophobic, so I didn’t actually go into a coffin. But I did force myself into position in my office as if I were in a coffin. What are the boundaries? How limited is movement? What could you do to pass the time? I read several biographies of women who were in these types of situations, and they all discussed the boredom and isolation, among other things.